Entropy change of a Ni45.5Co4.5Mn37In13 single crystal studied by scanning calorimetry in high magnetic fields: Field dependence of the magnetocaloric effect

Daniel Bourgault (1) , Laureline Porcar (1) , S Rivoirard (2, 3) , Pierre Courtois (4) , Vincent Hardy (5)

1 NEEL - TPS - Thermodynamique et biophysique des petits systèmes
2 NEEL - Institut Néel
3 CRETA - Consortium de Recherches pour l'Emergence des Technologies Avancées
4 ILL - Institut Laue-Langevin
5 CRISMAT - Laboratoire de cristallographie et sciences des matériaux

By using differential scanning calorimetry, direct entropy variations have been recorded along the martensitic transformation of a Ni45.5Co4.5Mn37In13 single crystal in various magnetic fields. A large negative magnetocaloric effect associated to the transformation from virtually non-magnetic martensite to ferromagnetic austenite coexists with a weaker, positive effect related to the Curie transition in the latter phase. It is shown that the field-dependence of the maximum isothermal entropy change can be modelized by taking into account the interplay of both magnetocaloric contributions, as well as the intrinsic width of the martensitic transformation.

Domaines: Physique [physics]

Daniel Bourgault, Laureline Porcar, S Rivoirard, Pierre Courtois, Vincent Hardy. Entropy change of a Ni45.5Co4.5Mn37In13 single crystal studied by scanning calorimetry in high magnetic fields: Field dependence of the magnetocaloric effect. Applied Physics Letters, 2015, 107 (9), pp.092403. ⟨10.1063/1.4929950⟩. ⟨hal-01199806⟩